Centella asiatica was extracted by methanol. The assay content of triterpenes in the extract was 0.12 % asiatic acid, 0.54 % madecassic acid, 0.25 % asiaticoside and 1.02 % madecassoside. The extract was complexed with hydroxypropyl-b-cyclodextrin (HP-b-CD) and formulated with Eudragit E100, glycerol, PEG 400, copovidone, ethanol and purified water. A clear yellowish solution (F1-F8) was obtained. The formulations had a pH of 5.5-6.0 with viscosity in the range of 20-60 mPa s, surface tension 20.3-24.6 mN m -1 and contact angle less than 20°. The amount of PEG 400 and copovidone affected the film and spreadability. The content of triterpenes in the spray formulation was close to 100 % compared to triterpenes in the extract. The skin irritation study indicated that the formulation was non-irritating in a rat model. An in vivo excision wound healing model showed that wound excision was completely healed after 14 days.

The anoikis-sensitization activity of imperatorin, an active furanocoumarin component of Angelica dahurica root, is reported herein for the first time. The present study demonstrated that the imperatorin treatment at sub-toxic concentrations enhanced human lung cancer H23 cell apoptosis after detachment. A Western blot analysis showed that imperatorin significantly enhanced the p53 protein level, which subsequently down-regulated Mcl-1 protein and up-regulated Bax, while it had a minimal effect on Bcl-2 expression. In addition, an anchorage-independent growth assay was performed to support the anti-metastasis potential of imperatorin. Consistent with anoikis assay, imperatorin exhibited a strong inhibitory effect on the anchorage-independent growth of the cells. Further, this study demonstrated that imperatorin sensitizes anoikis in other lung cancer cells, namely, H292 and A549. Because anoikis was shown to be a critical hindrance in preventing cancer cell metastasis, the knowledge regarding such an activity and an underlying mechanism may lead to the development of this compound for a cancer therapy.

Cisplatin (CDDP) induces senescence characterized by senescence-associated secretory phenotypes (SASP) and the unfolded protein response (UPR). In this study, we investigated the proteins related to the UPR during the senescence cell fate. Strikingly, we found that one of the critical ER-resident proteins, GRP78/BiP, was significantly altered. Here we show that GRP78 levels differentially expressed depending on non-small lung cancer subtypes. GRP78 indeed regulates the evasion of senescence in adenocarcinoma A549 cells, in which the increased GRP78 levels enable them to re-proliferate after CDDP removal. Conversely, GRP78 is downregulated in the senescence H460 cells, making them lacking senescence evasion capability. We observed that the translational regulation critically contributed to the GRP78 protein levels in CDDP-induces senescence. Furthermore, the increased GRP78 level during senescence confers resistance to senolytic drug, Bortezomib, as observed by a twofold increase in IC50 in A549 senescence cells compared to the wild-type. This observation is also consistent in the cells that have undergone genetic manipulation by transfection with pcDNA3.1(+)-GRP78/BiP plasmids and pSpCas9(BB)-2A-Puro containing guide RNA sequence targeting GRP78 exon 3 to induce the overexpression and downregulation of GRP78 in H460 cells, respectively. Our findings reveal a unique role of GRP78 on the senescence evasion cell fate and senolytic drug resistance after cisplatin-based chemotherapy.

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